The Evoc Hydration Bladder Kit is perfectly designed to work in conjunction with your Evoc hydration pack. It is made from TPU and is both BPA and PVC-free. In other words, it won't absorb the taste of your drink, which means your water will always taste fresh. The tube connects to the bladder via a simple quick-connect. The mouthpiece features a lock so that you don't inadvertently drench yourself in drink. For easy fill and refill, a slide-lock opens to a full-width opening. The Evoc Hydration Bladder Kit is available in one color and in either 2 or 3 liter options.